# -*- coding: utf-8 -*-

from rest_framework import serializers
from rest_framework.fields import empty
from rest_framework.request import Request
from rest_framework.serializers import ModelSerializer
from django.utils.functional import cached_property
from rest_framework.utils.serializer_helpers import BindingDict
from taggit.serializers import TagListSerializerField, TaggitSerializer
import reversion

from apps.sys.models import User
from django_restql.mixins import DynamicFieldsMixin


class CustomModelSerializer(TaggitSerializer, DynamicFieldsMixin, ModelSerializer):
    """
    增强DRF的ModelSerializer，可自动更新模型的审计字段记录
    """

    tags = TagListSerializerField(required=False, allow_empty=True)

    # 创建人的审计字段名称, 默认creator, 继承使用时可自定义覆盖
    creator_field_id = "creator"
    creator_name = serializers.SlugRelatedField(
        slug_field="name", source="creator", read_only=True
    )
    # 数据所属部门字段
    dept_belong_id_field_name = "dept_belong_id"
    # 添加默认时间返回格式
    create_time = serializers.DateTimeField(
        format="%Y-%m-%d %H:%M:%S", required=False, read_only=True
    )
    update_time = serializers.DateTimeField(format="%Y-%m-%d %H:%M:%S", required=False)

    # 修改人的审计字段名称, 默认modifier, 继承使用时可自定义覆盖
    modifier_field_id = "modifier"
    modifier_name = serializers.SerializerMethodField(read_only=True)

    def get_modifier_name(self, instance):
        if not hasattr(instance, "modifier"):
            return None
        queryset = (
            User.objects.filter(id=instance.modifier)
            .values_list("name", flat=True)
            .first()
        )
        if queryset:
            return queryset
        return None

    def __init__(self, instance=None, data=empty, request=None, **kwargs):
        super().__init__(instance, data, **kwargs)
        self.request: Request = request or self.context.get("request", None)

    def save(self, **kwargs):
        return super().save(**kwargs)

    def create(self, validated_data):
        if self.request:
            if self.creator_field_id in self.fields.fields:
                validated_data[self.creator_field_id] = self.request.user

            if (
                self.dept_belong_id_field_name in self.fields.fields
                and validated_data.get(self.dept_belong_id_field_name, None) is None
            ):
                validated_data[self.dept_belong_id_field_name] = getattr(
                    self.request.user, "dept_id", None
                )
        return super().create(validated_data)

    @reversion.create_revision(manage_manually=False, atomic=True)
    def update(self, instance, validated_data):
        if self.request:
            if hasattr(self.instance, self.modifier_field_id):
                validated_data[self.modifier_field_id] = self.get_request_user_id()
                if isinstance(validated_data.get("prefix"), int):
                    validated_data["prefix"] += 1
        return super().update(instance, validated_data)

    def get_request_username(self):
        if getattr(self.request, "user", None):
            return getattr(self.request.user, "username", None)
        return None

    def get_request_name(self):
        if getattr(self.request, "user", None):
            return getattr(self.request.user, "name", None)
        return None

    def get_request_user_id(self):
        if getattr(self.request, "user", None):
            return getattr(self.request.user, "id", None)
        return None
